Amorphous steel
DOI: 10.1063/1.4796626
Amorphous steel for structural applications has been fabricated by scientists at Oak Ridge National Laboratory. Some amorphous iron-based alloys were made previously, but their cross sections were limited to about 4 mm. Adding a small amount of yttrium, which frustrates the onset of crystallization as the liquid metal solidifies, allows the new alloys to be cast, using commercial techniques, in 12-mm-diameter rods. The new glassy steel is more than twice as hard as the best ultra-high-strength conventional steel, and yet is less dense. In addition, the steel is ferromagnetic at cryogenic temperatures but paramagnetic at room temperature, a property the researchers say could open up new industrial applications. (Z. P. Lu et al., Phys. Rev. Lett. 92, 245503, 2004 http://dx.doi.org/10.1103/PhysRevLett.92.245503 .)
